首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   5638篇
  免费   580篇
  国内免费   27篇
电工技术   115篇
综合类   15篇
化学工业   1479篇
金属工艺   141篇
机械仪表   123篇
建筑科学   210篇
矿业工程   18篇
能源动力   390篇
轻工业   538篇
水利工程   66篇
石油天然气   138篇
无线电   718篇
一般工业技术   1067篇
冶金工业   222篇
原子能技术   42篇
自动化技术   963篇
  2024年   16篇
  2023年   174篇
  2022年   290篇
  2021年   396篇
  2020年   297篇
  2019年   302篇
  2018年   387篇
  2017年   295篇
  2016年   338篇
  2015年   240篇
  2014年   293篇
  2013年   490篇
  2012年   295篇
  2011年   324篇
  2010年   236篇
  2009年   235篇
  2008年   184篇
  2007年   144篇
  2006年   132篇
  2005年   138篇
  2004年   107篇
  2003年   72篇
  2002年   66篇
  2001年   71篇
  2000年   60篇
  1999年   67篇
  1998年   78篇
  1997年   44篇
  1996年   47篇
  1995年   23篇
  1994年   29篇
  1993年   39篇
  1992年   27篇
  1991年   18篇
  1990年   24篇
  1989年   30篇
  1988年   23篇
  1987年   11篇
  1986年   20篇
  1985年   17篇
  1984年   17篇
  1983年   15篇
  1982年   13篇
  1981年   13篇
  1980年   13篇
  1979年   9篇
  1978年   14篇
  1977年   11篇
  1976年   18篇
  1974年   12篇
排序方式: 共有6245条查询结果,搜索用时 187 毫秒
51.
Geologists interpret seismic data to understand subsurface properties and subsequently to locate underground hydrocarbon resources. Channels are among the most important geological features interpreters analyze to locate petroleum reservoirs. However, manual channel picking is both time consuming and tedious. Moreover, similar to any other process dependent on human intervention, manual channel picking is error prone and inconsistent. To address these issues, automatic channel detection is both necessary and important for efficient and accurate seismic interpretation. Modern systems make use of real-time image processing techniques for different tasks. Automatic channel detection is a combination of different mathematical methods in digital image processing that can identify streaks within the images called channels that are important to the oil companies. In this paper, we propose an innovative automatic channel detection algorithm based on machine learning techniques. The new algorithm can identify channels in seismic data/images fully automatically and tremendously increases the efficiency and accuracy of the interpretation process. The algorithm uses deep neural network to train the classifier with both the channel and non-channel patches. We provide a field data example to demonstrate the performance of the new algorithm. The training phase gave a maximum accuracy of 84.6% for the classifier and it performed even better in the testing phase, giving a maximum accuracy of 90%.  相似文献   
52.
The bivariate distributions are useful in simultaneous modeling of two random variables. These distributions provide a way to model models. The bivariate families of distributions are not much widely explored and in this article a new family of bivariate distributions is proposed. The new family will extend the univariate transmuted family of distributions and will be helpful in modeling complex joint phenomenon. Statistical properties of the new family of distributions are explored which include marginal and conditional distributions, conditional moments, product and ratio moments, bivariate reliability and bivariate hazard rate functions. The maximum likelihood estimation (MLE) for parameters of the family is also carried out. The proposed bivariate family of distributions is studied for the Weibull baseline distributions giving rise to bivariate transmuted Weibull (BTW) distribution. The new bivariate transmuted Weibull distribution is explored in detail. Statistical properties of the new BTW distribution are studied which include the marginal and conditional distributions, product, ratio and conditional momenst. The hazard rate function of the BTW distribution is obtained. Parameter estimation of the BTW distribution is also done. Finally, real data application of the BTW distribution is given. It is observed that the proposed BTW distribution is a suitable fit for the data used.  相似文献   
53.
Artificial Intelligence Review - Visual object tracking has become one of the most active research topics in computer vision, and it has been applied in several commercial...  相似文献   
54.
The Journal of Supercomputing - Multiple tasks arrive in the distributed systems that can be executed in either parallel or sequential manner. Before the execution, tasks are scheduled prioritywise...  相似文献   
55.
Neural Computing and Applications - A multi-robot-based fault detection system for railway tracks is proposed to eliminate manual human visual inspection. A hardware prototype is designed to...  相似文献   
56.
Microsystem Technologies - This paper presents a critical analysis of the meta-heuristic techniques used in various researches on the optimisation of photovoltaic (PV) parameters, which involves...  相似文献   
57.
Neural Computing and Applications - This paper investigates the ability of deep neural networks (DNNs) to improve the automatic recognition of dysarthric speech through the use of convolutional...  相似文献   
58.
We propose a novel pose-invariant face recognition approach which we call Discriminant Multiple Coupled Latent Subspace framework. It finds the sets of projection directions for different poses such that the projected images of the same subject in different poses are maximally correlated in the latent space. Discriminant analysis with artificially simulated pose errors in the latent space makes it robust to small pose errors caused due to a subject’s incorrect pose estimation. We do a comparative analysis of three popular latent space learning approaches: Partial Least Squares (PLSs), Bilinear Model (BLM) and Canonical Correlational Analysis (CCA) in the proposed coupled latent subspace framework. We experimentally demonstrate that using more than two poses simultaneously with CCA results in better performance. We report state-of-the-art results for pose-invariant face recognition on CMU PIE and FERET and comparable results on MultiPIE when using only four fiducial points for alignment and intensity features.  相似文献   
59.
This paper proposes a method for designing robust H?? static output feedback stabilization of Takagi-Sugeno (T-S) fuzzy systems under actuator saturation. In this paper, the input saturation is represented by a polytopic model and the modeling error is assumed a norm-bounded uncertainty. A set invariance condition for robust H?? static output feedback system under actuator saturation is first established. Then, the estimation of the largest domain of attraction for the system is formulated and solved as a Linear Matrix Inequality (LMI) optimization problem. Two examples are used to demonstrate the effectiveness of the proposed design method.  相似文献   
60.
One of the most common difficulties arising when building roads and railway lines in seacoast areas is the high watertable in these regions. Among the applied dewatering methods, the most effective seems to be vertical drainage permanently lowering the level of underground water. Application of this method has also been carried out in Iraq. One should consider the fact that the vertical drainage method permits dewatering of not only the existing targets but also the areas designated for new construction. Lowering the watertable allows stabilization of the bed, and that secures stability and resistance of the foundation. The vertical drainage system depends upon underground water intake flowing to the drains from the directions of watershed in order to avoid its damming up under the building site. Dewatering according to the drainage system is much more efficient than open drain systems applied until now. From the technical point of view the system under discussion is much easier to operate, it consumes, less time and at the same time limits the number of people employed, workmen, engineers, and engineering equipment. Moreover, it has the advantage of dispensing with the expenses connected with the construction of passes and bridges, which are indispensable when the open drain ditches systems are applied. One opening of the proposed drainage may drain about 50 ha. The method is much more economical and much more efficient provided the whole drainage system is properly planned, and properly executed.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号